cleft lip

lip (lip)

1. the upper or lower fleshy margin of the mouth.

2. any liplike part; labium.

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cleft lip  a congenital cleft or defect in the upper lip.

glenoid lip  a ring of fibrocartilage joined to the rim of the glenoid cavity.

Hapsburg lip  a thick, overdeveloped lower lip that often accompanies Hapsburg jaw.

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cleft lip n. A congenital facial deformity of the lip, usually the upper lip, due to a mesodermal deficiency or to a failure of merging in one or more of the embryologic processes that form the lip; it is frequently associated with cleft tooth socket and cleft palate. Also called cheiloschisis, harelip.

cleft lip Left: unilateral cleft lip Right: bilateral cleft lip

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cleft lip,

a congenital anomaly consisting of one or more clefts in the upper lip that result from the failure in the embryo of the maxillary and median nasal processes to close. Treatment is surgical repair in infancy. Also called harelip. See also cleft palate.

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cleft (kleft),

n a longitudinal fissure of opening.

cleft, facial,

n the fissures along the embryonal lines of the junction of the maxillary and lateral nasal processes; usually extend obliquely from the nasal ala to the outer border of the eye (canthus).

cleft, gingival,

n a cleft of the marginal gingiva; may be caused by many factors, such as incorrect toothbrushing, a breakthrough to the surface of pocket formation, or faulty tooth positions, and may resemble a V-shaped notch.

cleft lip,

n a congenital anomaly of the face caused by the failure of fusion between embryonic maxillary and medial nasal processes.

Cleft lip and palate.

cleft, occult,

n See submucous cleft.

cleft, operated,

n (postoperative cleft), a cleft that has been surgically repaired.

cleft palate,

n a congenital anomaly of the oral cavity caused by the failure of fusion between the embryonic palatal shelves.

cleft palate, alveolar graft,

n a bone graft placed at the site of a hard palate cleft before teeth have an opportunity to erupt through the gingiva tissue. It creates the architecture necessary for normal eruption of the maxillary teeth and provides support for adjacent teeth. It may also eliminate the need for prosthetic intervention in the future.

cleft palate, hard palate graft,

n a bone graft used to block the oronasal passage in order to facilitate breathing in children with hard palate clefts.

cleft palate prosthesis,

n See prosthesis, cleft palate.

cleft, postoperative,

n See cleft, operated.

cleft, Stillman's,

n the small fissures extending apically from the midline of the gingival margin in teeth subjected to trauma. Although these clefts may be found in traumatism, they are not necessarily diagnostic of occlusal trauma.

cleft, submucous,

n See submucous cleft.

cleft, unoperated,

n a cleft of the palate that has not been surgically repaired.

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lip,

n 1. either the upper or lower structure surrounding the opening of the oral cavity.
2. a rimlike structure bordering a cavity or groove.

lip biting,

n an oral habit in which either lip is placed between the teeth with more or less forcible application of the teeth to the lips.

lip, cleft,

n See harelip.

lip, congenital cleft,

n See harelip.

lip, double,

n a redundant fold of tissue on the mucosal side of the upper lip that gives the appearance of a second lip and that may become accentuated by habitually being sucked between the teeth.

lip line, high,

n the greatest height to which the lip is raised in normal function or during the act of smiling broadly.

lip line, low,

n the lowest position of the lower lip during the act of smiling or voluntary retraction. The lowest position of the upper lip at rest.

lip pits (congenital lip fistulas),

n.pl the congenital depressions, usually bilateral and symmetrically placed, on the vermilion portion of the lower lip. These pits may be circular or may be present as a transverse slit. The depression represents a blind fistula that penetrates downward into the lower lip to a depth of 0.5 to 2.5 cm. They often exude viscid saliva on pressure.

lip retractor,

n a device to retract the lips when taking intraoral photographs.

lip, structures of,

n.pl See vermilion border; vestibule, labial; frenum, labial.

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cleft

a fissure or longitudinal opening, especially one occurring during embryonic development.

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branchial c's

the slit-like openings in the gills of fish between the branchial arches; also, the homologous branchial grooves between the branchial arches of mammalian embryos.

cleft chin

occasionally seen in cattle particularly Herefords. There is a notch at the mandibular symphysis and the central incisors may be directed centrally.

frog cleft

the sagittal cleft in the frog of the horse's foot.

glottic cleft

entrance to the larynx; called also rima glottidis.

infundibular cleft

common opening of the auditory tubes in birds.

interdigital cleft

separates the hooves.

cleft lip

a defect in fusion between the central prolabium and one or both lateral mesodermal masses. Most common in dogs of the brachycephalic breeds; may be inherited or caused by environmental factors. Often combined with defects in the palate. Called also primary cleft palate, harelip, cheiloschisis.

Congenital fissure, or split, may involve the hard or soft palate. A common cause of nasal regurgitation in neonates, especially foals. Known to be inherited in some breeds of cattle and dogs, particularly brachycephalic breeds. Called also secondary cleft palate, palatoschisis.

Cleft lip (harelip) in a calf. By permission from Blowey RW, Weaver AD, Diseases and Disorders of Cattle, Mosby, 1997

cleft palate

see cleft lip (above). Also occurs commonly in diseases manifest with arthrogryposis, both hereditary as in Charolais cattle and with lupine-induced crooked calf.

Rathke cleft

see rathke's pouch.

cleft tongue

the anterior portion is divided by a longitudinal cleft.

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cleft lip

Embryology A congenital defect characterized by a failure in the fusion of the upper lip; often associated with cleft palate. See Cleft palate.